fix grep matching device in routes

[zhangzujian]

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What type of this PR

• Bug fixes

Which issue(s) this PR fixes:

Fix incorrect grep matching introduced in #1983 :

[root@k8s ~]# echo '114.114.114.114 via 192.168.152.1 dev enp1s0 src 192.168.155.30 uid 0' | grep -oE 'dev [^\s]+' | awk '{print $2}'
enp1
[root@k8s ~]# echo '114.114.114.114 via 192.168.152.1 dev enp1s0 src 192.168.155.30 uid 0' | grep -oE 'dev .+' | awk '{print $2}'
enp1s0